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Long-wave infrared emission properties of strain-balanced InAs/In_(x)Ga_(1-x)As_(y)Sb_(1-y)type-Ⅱsuperlattice on different substrates

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Rare Metals 2024年第7期43卷 3194-3204页

作者： Chao Shi Xuan Fang Hong-Bin Zhao Deng-Kui Wang Xi Chen Dan Fang Dong-Bo Wang Xiao-Hua Wang Jin-Hua Li state key {2. of High Power Semiconductor Lasers School of PhysicsChangchun University of Science and TechnologyChangchun 130022China state key {2. of Advanced Materials for Smart sensing China General Research Institute for Nonferrous MetalsBeijing 100088China Department of Opto-Electronic Information science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

High-performance type-Ⅱsuperlattices ofⅢ-Ⅴsemiconductor materials play an important role in the development and application of infrared optoelectronic *** the quality of epitaxial materials and clarifying the luminescent mechanism are of great significance for practic al applic *** this work,strain-balanced and high-quality In As/In_(x)Ga_(1-x)As_(y)Sb_(1-y)superlattices without lattice mismatch were achieved on InAs and GaSb substrates *** grown on In As substrate could exhibit higher crystal quality and surface flatness based on high-resolution X-ray diffraction(HRXRD)and atomic force microscopy(AFM)measurements'***,the strain distribution phenomenon from geometric phase analysis indicates that fluctuations of alloy compositions in superlattices on GaSb substrate are more *** addition,the optical properties of superlattices grown on different substrates are discussed *** of the difference in fluctuations of element composition and interface roughness of superlattices on different substrates,the superlattices grown on In As substrate would have higher integral intensity and narrower full-width at half maximum of long-wave infrared ***,the thermal quenching of emission intensity indicates that the superlattices grown on the In As substrate have better recombination ability,which is beneficial for increasing the operating temperature of infrared optoelectronic devices based on this type of superlattices.

关键词： Photoluminescence Alloy compositions fluctuations InAs(Sb)/In_(x)Ga_(1-x)As_(y)Sb_(1-y) Type-Ⅱsuperlattice Substrate

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Comparison of bulk snow density measurements using different methods

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Advances in Climate Change Research 2024年第4期15卷 658-668页

作者： Hang SU Xin-Yue ZHONG Bin CAO Yuan-Tao HU Lei ZHENG Tingjun ZHANG state key {2. of Water Resources and Hydropower Engineering science Wuhan UniversityWuhan 430072China key laboratory of {2. sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China key laboratory of Tibetan Plateau Earth System Environment and ResourcesNational Tibetan Plateau Data CenterInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Climate Centre of Shaanxi Province Xi'an71000China School of Geospatial Engineering and science Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China key laboratory of Westem China's Environmental Systems(Ministry of Education).College of Earth and Environmental {2.s Lanzhou Universiny Lanzhou 730000China

Snow density is one of the basic properties used to describe snow cover characteristics,and it is critical for remote sensing retrieval,water resources assessment and modeling *** are many instruments available to measure snow density in ***,there are mea-surement errors of snow density for bulk and layers or gravimetric and electronic instruments,which may affect the accuracy of remote sensing retrieval and model *** in China,due to the noticeable heterogeneity of snowpacks,it is necessary to evaluate in detail the performance and applicability of snow density instruments in different snowpack *** study evaluated the performance of different snow density instruments:the Federal Sampler,the model VS-43 snow density cylinder(VS-43),the wedge snow density cutter(WC1000 and WC2.O),and the Snow *** average bulk snow density of all instrument measurements was set as the reference value for *** results showed that as compared with the reference,the VS-43 cylinder presented the best performance for bulk snow density measurement in the measured range with the lowest RMSE(11 kg m-3),BIAS(3 kg m-3),and MRE(1.6%).For layer observation,bulk snow density was overestimated by 8.1%with WC1000 and underestimated by 11.4%with Snow Fork which was the worst performance compared with the reference value,and there were greater measurement errors of snow density in the depth hoar than other snow *** with grassland,the uncertainty of snow density measurements was slightly lower in ***,the Federal Sampler and VS-43 cylinder are more suitable for bulk snow density measurement in deep snowpack regions across China,and it is recommended to use WC1000,WC2.0 and Snow Fork to measure the snow density of snow layers in the snow stratigraphy.

关键词： Snowdensity Measurement Uncertainty comparison

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A novel dual-channel thermo-optic locking method for the whispering gallery mode microresonator

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Chinese Physics B 2024年第5期33卷 438-444页

作者：范文杰刘文耀潘梓文王蓉刘来邢恩博周彦汝唐军刘俊 state key {2. of Dynamic Measurement Technology North University of ChinaTaiyuan 030051China Shanxi Province key laboratory of Quantum {2. and Precision Measurement North University of ChinaTaiyuan 030051China

Mode locking can be effectively achieved by using the thermo-optic effects in the whispering gallery mode(WGM)optical microcavity,without the help of external ***,it has the advantages of small size,low integration costs,and self-locking,which shows great potential for ***,the conventional single-channel microcavity thermal-locking method that relies solely on internal thermal balance will inevitably be disturbed by the external *** limitation affects the locking time and ***,in this paper,we propose a new method for closed-loop thermal locking of a dual-channel *** thermal locking of the signal laser and the thermal regulation of the control laser are carried out respectively by synchronously drawing a dual-path tapered *** theoretical model of the thermal dynamics of the dual-channel microcavity system is established,and the influence of the control-laser power on the thermal locking of the signal laser is *** deviation between the locking voltage of the signal laser and the set point value is used as a closed-loop feedback parameter to achieve long-term and highly stable mode locking of the signal *** results show that in the 2.63 h thermal-locking test,the locking stability is an order of magnitude higher than that of the single tapered *** solution addresses the issue of thermal locking being disrupted by the external environment,and offers new possibilities for important applications such as spectroscopy and micro-optical sensor devices.

关键词： optical microcavity thermo-optic locking thermal nonlinearity effect

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A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2.00 to 2.2.

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Journal of Arid Land 2024年第9期16卷 1163-1182页

作者： GUO Bing XU Mei ZHANG Rui LUO Wei School of Civil Engineering and Geomatics Shandong University of TechnologyZibo 255000China key laboratory of {2. sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China North China Institute of Aerospace Engineering Langfang 065000China

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade ***,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be ***,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2.00 to 2.2. and its driving *** results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River *** 2.00 to 2.2.,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability *** intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi *** 2.00 to 2.2.,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of *** gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the *** dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2.00 to 2.2.,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional *** above results could provide decision support for the ecological protection and restoration of the Y

关键词： ecological vulnerability spatio-temporal pattern gravity center migration trajectory interaction factors geodetector green index q-value

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Spatiotemporal variations in glacier area and surface velocity of the northern Antarctic Peninsula during 2.18-2.2.

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Advances in Climate Change Research 2024年第2期15卷 297-311页

作者： Yu-Long KANG Shi-Chang KANG Wan-Qin GUO Tao CHE Zong-Li JIANG Zhen-Feng WANG Qiang-Qiang XU Cheng-De YANG state key {2. of Cryospheric science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of sciences Beijing 100083China key laboratory of {2. sensing of Gansu Province Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Earth sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China

Ice sheet serves as a crucial indicator for assessing climate *** loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface ***,observations of seasonal variability of ice speed are limited,and glacier-area changes require multi-temporal *** study investigated the changes in area and surface velocities of∼375 glaciers on the northern Antarctic Peninsula(NAP)utilizing satellite images acquired by the Sentinel 1&2.satellites during *** results indicate that the glacier area reduced by approximately 166.1±44.2.km^(2.(-0.2.±0.1%per year)during the study period,with an acceleration after 2.2.(-0.4%±0.3%per year),and the most dramatic reduction happened on the eastern *** maximum annual ice speeds on the NAP generally exceeded 3500 m per year,while the ice speeds in 2.2. were the highest(exceeded 42.0 m per year).The ice speed variability in austral autumn was higher than in other seasons,meanwhile the summer ice speeds showed an increasing *** glacier G012.58E47018N,McNeile Glacier,glacier G2.9637E64094S and Drygalski Glacier showed the most remarkable ice speed variations represented by high daily velocities and strong fluctuations on their *** results demonstrated that the variations in glacier area and seasonal ice speed on the NAP were responsive to the ice-ocean-atmosphere ***,seasonal velocity and area variations should be considered when conducting accurate mass balance calculations,model validations and change mechanism analyses under climate warming scenarios.

关键词： Glacier area Seasonal ice speed Sentinel 1&2 Northern Antarctic Peninsula Ice-ocean-atmosphere processes

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Urban growth scenario projection using heuristic cellular automata in arid areas considering the drought impact

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Journal of Arid Land 2024年第4期16卷 580-601页

作者： TANG Xiaoyan FENG Yongjiu LEI Zhenkun CHEN Shurui WANG Jiafeng WANG Rong TANG Panli WANG Mian JIN Yanmin TONG Xiaohua College of Surveying&Geo-Informatics Tongji UniversityShanghai 200092China Shanghai key laboratory of Space Mapping and {2. sensing for Planetary Exploration Tongji UniversityShanghai 200092China

Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future *** simulation and projection based on cellular automata(CA)models is important to achieve sustainable urban development in arid *** developed a new CA model using bat algorithm(BA)named bat algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model by considering drought constraint to accurately delineate urban growth patterns and project future scenarios of Urumqi City and its surrounding areas,located in Xinjiang Uygur Autonomous Region,*** calibrated the BA-POO-CA model for the drought-prone study area with 2.00 and 2.10 data and validated the model with 2.10 and 2.2. data,and finally projected its urban scenarios in *** results showed that BA-POO-CA model yielded overall accuracy of 97.70%and figure-of-merits(FOMs)of 35.50%in 2.10,and 97.70%and 2..70%in 2.2.,*** inclusion of drought intensity factor improved the performance of BA-POO-CA model in terms of FOMs,with increases of 5.50%in 2.10 and 7.90%in 2.2. than the model excluding drought intensity *** suggested that the urban growth of Urumqi City was affected by drought,and therefore taking drought intensity factor into account would contribute to simulation *** BA-POO-CA model including drought intensity factor was used to project two possible scenarios(i.e.,business-as-usual(BAU)scenario and ecological scenario)in *** the BAU scenario,the urban growth dominated mainly in urban fringe areas,especially in the northern part of Toutunhe District,Xinshi District,and Midong *** exceptional and extreme drought areas as a spatial constraint,the urban growth was mainly concentrated in the"main urban areas-Changji-Hutubi"corridor urban pattern in the ecological *** results of this research can help to adjust urban planning and development *** mode

关键词： bat algorithm cellular automata(CA) probability-of-occurrence drought intensity algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model arid areas

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Spatio-Temporal Characteristics of Heavy Precipitation Forecasts from ECMWF in Eastern China

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Journal of Tropical Meteorology 2024年第1期30卷 29-41页

作者：徐同谭燕顾问 Shanghai Typhoon Institute and Key Laboratory of Numerical Modeling for Tropical Cyclone of China Meteorological AdministrationShanghai 200030 China state key {2. of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100080 China Shanghai Ecological Forecasting and remote sensing Center Shanghai 200030 China

This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method for Object-based Diagnostic Evaluation(MODE-TD). A total of 2. heavy rainfall cases occurring between 2.18 and 2.2. are selected for analysis. Using Typhoon “Rumbia” as a case study, the paper illustrates how the MODE-TD method assesses the overall simulation capability of models for the life history of precipitation systems. The results of multiple tests with different parameter configurations reveal that the model underestimates the number of objects’ forecasted precipitation tracks, particularly at smaller radii. Additionally, the analysis based on centroid offset and area ratio tests for different classified precipitation objects indicates that the model performs better in predicting large-area, fast-moving, and longlifespan precipitation objects. Conversely, it tends to have less accurate predictions for small-area, slow-moving, and shortlifespan precipitation objects. In terms of temporal characteristics, the model overestimates the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. In terms of temporal characteristics, the model tends to overestimate the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. Overall, the model provides more accurate predictions for the duration and dissipation of precipitation objects with large-area or long-lifespan(such as typhoon precipitation) while having large prediction errors for precipitation objects with small-area or short-lifespan. Furthermore, the model’s simulation results regarding the generation of precipitation objects show that it performs relati

关键词： MODE-TD ECMWF heavy precipitation Eastern China

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Strain-promoted S-arylation and alkenylation of sulfinamides using arynes and cyclic alkynes

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science China Chemistry 2024年第3期67卷 928-935页

作者： Xi Zou Boming Shen Gao-lin Li Qian Liang Yanhua Ouyang Binghe Yang Peiyuan Yu Bing Gao state key {2. of Chemo/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringInstitute of Chemical Biology and NanomedicineHunan UniversityChangsha 410082China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China

The conversion of commercially available chiral sulfinamides into pharmaceutically useful chiral sulfoximines via direct SIVfunctionalization is synthetically attractive but challenging due to the competitive reaction of N-functionalization. Herein, we disclose a novel strain-release strategy to access stereospecific and chemoselective SIV-arylation and alkenylation of sulfinamides using arynes and strained cyclic alkynes. This method tolerates an unprecedented chemical diversity of functional groups attached to the nitrogen center(N-R). The origin of the high SIV-selectivity is elucidated by density functional theory calculations, suggesting a stepwise mechanism for the aryne substrates and a concerted mechanism for the cyclic alkynes.

关键词： arylation alkenylation sulfoximines sulfinamides arynes

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Impact crater recognition methods:A review

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science China Earth sciences 2024年第6期67卷 1719-1742页

作者： Dong CHEN Fan HU Liqiang ZHANG Yunzhao WU Jianli DU Jiju PEETHAMBARAN College of Civil Engineering Nanjing Forestry UniversityNanjing 210037China Department of Geography State Key Laboratory of Remote Sensing ScienceFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China key laboratory of Space Object and Debris Observation Chinese Academy of SciencesNanjing 210023China Department of Mathematics and Computing science Saint Mary’s UniversityHalifaxNS B3H 3C3Canada

Impact craters are formed due to the high-speed collisions between small to medium-sized celestial *** is the most significant driving force in the evolution of celestial bodies,and the impact craters provide crucial insights into the formation,evolution,and impact history of celestial *** this paper,we present a detailed review of the characteristics of impact craters,impact crater remote sensing data,recognition algorithms,and applications related to impact *** first provide a detailed description of the geometric texture,illumination,and morphology characteristics observed in remote sensing data of *** we summarize the remote sensing data and cataloging databases for the four terrestrial planets(i.e.,the Moon,Mars,Mercury,and Venus),as well as the impact craters on ***,we study the advancement achieved in the traditional methods,machine learning methods,and deep learning methods applied to the classification,segmentation,and recognition of impact ***,based on the analysis results,we discuss the existing challenges in impact crater recognition and suggest some ***,we explore the implementation of impact crater detection algorithms and provide a forward-looking perspective.

关键词： Terrestrial planets Deep space exploration Impact crater Impact crater recognition Deep learning

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Combining anodic alcohol oxidative coupling for C-C bond formation with cathodic ammonia production

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National science Review 2024年第5期11卷 217-226页

作者： Leitao Xu Wei Chen Cairong Wang Wenjie Wu Yelin Yao Zhifeng Huang Jingcheng Wu Ming Yang Yandong Wu Dianke Xie Yuqin Zou Shuangyin Wang state key {2. of Chemo/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringAdvanced Catalytic Engineering Research Center of the Ministry of Education Hunan University

Electrocatalytic oxidation of alcohols using heterogeneous catalysts is a promising aqueous, energy-efficient and environmentally friendly approach, especially for coupling different alcohols to prolong the carbon chain via co-oxidation. Precisely regulating critical steps to tailor electrode materials and electrolyte composition is key to selectively coupling alcohols for targeted synthesis. However, selectively coupling different alcohols remains challenging due to the lack of effective catalyst and electrolyte design promoting specific pathways. Herein, we demonstrate a paired electrolysis strategy for combining anodic oxidative coupling of ethanol（EtOH） and benzyl alcohol（PhCH2.H） to synthesize cinnamaldehyde（CAL） and cathodic ammonia production. The strategies involve:（i） utilizing the salt-out effect to balance selective oxidation and coupling rates;（ii） developing platinum-loaded nickel hydroxide electrocatalysts to accelerate intermediate coupling kinetics;（iii） introducing thermodynamically favorable nitrate reduction at the cathode to improve coupling selectivity by avoiding hydrogenation of products while generating valuable ammonia instead of hydrogen. We achieved 85% coupling selectivity and 2.8 μmol/h NH3productive rate at 100 m A/cm2.ith a low energy input（～1.63 V）. The membrane-free, low energy, scalable approach with a wide substrate scope highlights promising applications of this methodology. This work advances heterogeneous electrocatalytic synthesis through rational design principles that integrate anodic oxidative coupling with cathodic nitrate reduction reactions, having synergistic effects on efficiency and selectivity.

关键词： anodic alcohol oxidative coupling C–C bond formation cinnamaldehyde cathodic ammonia production

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